EP 0244425 A4 19871112 - MULTIPLE-STAGE COAL SEAM FRACING METHOD.
Title (en)
MULTIPLE-STAGE COAL SEAM FRACING METHOD.
Title (de)
MEHRSTUFIGES VERFAHREN ZUM KOHLENABBAU NACH DEN NUTZSCHICHTEN.
Title (fr)
PROCEDE DE FRACTURATION ETAGEE DE VEINES DE CHARBON.
Publication
Application
Priority
US 78832485 A 19851017
Abstract (en)
[origin: US4665990A] An improved method of multiple-stage hydraulic fracturing of coal seams to improve the rate and total recovery of gas therefrom. In one aspect, the improvement comprises completing the well with 7-inch or larger casing and 31/2 inch or larger tubing. In another aspect, the stagewise fracturing is continued until the following quantity of 60-140 mesh proppants has been deposited in the formation: -for 5 </= h < 10, m >/= 500,000; -for 10 </= h < 15, m >/= 750,000; -for 15 </= h < 20, m >/= 1,000,000; -for 20 </= h < 25, m >/= 2,000,000; and -for h >/= 25, m >/= 3,000,000; - wherein h is the vertical thickness of the coal seam in feet and m is the minimum quantity of the fine proppants in pounds deposited therein. In another aspect, a coal seam fractured by the multiple-stage method is refractured after producing or shutting in the well for a period of time to permit closure of the fractures on the proppant placed therein in the earlier multiple-stage fracturing of the coal seam.
IPC 1-7
IPC 8 full level
C09K 8/72 (2006.01); E21B 43/00 (2006.01); E21B 43/26 (2006.01); E21B 43/267 (2006.01); E21B 43/27 (2006.01)
CPC (source: EP KR SE US)
C09K 8/72 (2013.01 - EP US); E21B 43/006 (2013.01 - EP KR US); E21B 43/267 (2013.01 - EP KR SE US); E21B 43/27 (2020.05 - EP KR SE US); C09K 8/72 (2013.01 - KR)
Citation (search report)
[X] BE 901244 A 19850610 - PERLMAN WILLIAM
Designated contracting state (EPC)
IT
DOCDB simple family (publication)
US 4665990 A 19870519; AT A902586 A 19910515; AU 573987 B2 19880623; AU 6224186 A 19870505; BE 903953 A 19860630; BG 48574 A3 19910315; CA 1222942 A 19870616; CN 86107208 A 19870701; CS 749886 A3 19920318; DE 3633020 A1 19870423; EP 0244425 A1 19871111; EP 0244425 A4 19871112; ES 551298 A0 19861116; ES 8701293 A1 19861116; FR 2595753 A1 19870918; FR 2595753 B1 19910830; GB 2181767 A 19870429; GB 2181767 B 19880622; GB 2184470 A 19870624; GB 2184470 B 19880622; GB 2184471 A 19870624; GB 2184471 B 19880622; GB 8624798 D0 19861119; GB 8703893 D0 19870325; GB 8703894 D0 19870325; HU 195986 B 19880829; HU T43879 A 19871228; IN 168693 B 19910518; JP S62502350 A 19870910; KR 880700148 A 19880220; KR 910003096 B1 19910518; MY 100237 A 19900712; MY 100701 A 19910131; MY 100702 A 19910131; MY 101413 A 19911118; NL 8503332 A 19870518; PL 261911 A1 19870810; SE 8702542 D0 19870617; SE 8702542 L 19870617; WO 8702410 A1 19870423; YU 176586 A 19881031; YU 45371 B 19920528; ZA 867547 B 19870527
DOCDB simple family (application)
US 78832485 A 19851017; AT 902586 A 19860812; AU 6224186 A 19860813; BE 216071 A 19851230; BG 8000187 A 19870603; CA 496679 A 19851202; CN 86107208 A 19861016; CS 749886 A 19861016; DE 3633020 A 19860929; EP 86905106 A 19860813; ES 551298 A 19860128; FR 8519296 A 19851227; GB 8624798 A 19861016; GB 8703893 A 19870219; GB 8703894 A 19870219; HU 4086 A 19860813; IN 876MA1986 A 19861110; JP 50445386 A 19860813; KR 870700523 A 19870617; MY UI19870529 A 19870423; MY UI19870530 A 19870423; MY UI19870531 A 19870423; MY UI19870532 A 19870423; NL 8503332 A 19851203; PL 26191186 A 19861017; SE 8702542 A 19870617; US 8601645 W 19860813; YU 176586 A 19861017; ZA 867547 A 19861002